Roof membrane and insulation removing device

ABSTRACT

A device for stripping a waterproof rubber membrane and foam insulation from a roof. The device includes a wheeled frame having a pair of handlebars at its rear for steering by a walking attendant. A first cutting blade is secured to the front of the wheeled frame and is rotatable about a substantially vertical axis. A pair of second cutting blades is secured to the front of the wheeled frame on opposite sides of the first cutting blade. Each one of the second cutting blades is rotatable about a substantially horizontal axis. A prime mover is secured to the frame for rotating the first cutting blade and the second cutting blades.

FIELD OF THE INVENTION

The present invention relates generally to cutlery and, moreparticularly, to cutting tools mounted on vehicles moved during cutting.

BACKGROUND OF THE INVENTION

Impermeable rubber membranes positioned atop foam insulation arecommonly used to make watertight roofs on commercial buildings. Overtime, ultraviolet radiation, temperature changes and acid raindeteriorate these membranes, necessitating their replacement. Theprincipal tool used to accomplish this task is a heavyweight, tippingthe scales at about half a ton, which cuts membrane-anchoring screws andrips up membrane with a sawing blade. Unfortunately, this tool alsovibrates metal roof decking, sometimes to the point of buckling, andshakes loose ceiling tiles on the interior of buildings. For thisreason, roofers sometimes employ handheld, but powered, screwdrivers andshears to unfasten anchoring screws so that a roof membrane can belifted and replaced. The process of removing a membrane, however, isslow with handheld tools.

SUMMARY OF THE INVENTION

In light of the problems associated with the known tools for detachingold membranes and foam insulation from building roofs, it is a principalobject of the invention to provide a device that not only eliminates thehandwork involved in detaching a membrane and insulation from a roof,but quickly accomplishes this task without damaging the steel deckingthat supports the membrane and insulation. The device cuts the membraneand insulation, measuring from one inch to eight inches thick,vertically and horizontally into elongated strips that are easy tohandle. After cutting, the device gathers the strips for easy disposal.Any screws employed to secure the membrane and insulation are severed asthe membrane and insulation are simultaneously cut and lifted from aroof.

It is a further object of the present invention to provide a device ofthe type described that, as a membrane and insulation are being cut,severs any screws employed to secure the membrane and insulation inplace. The tasks of cutting membrane, insulation and fasteners areaccomplished in a single pass with minimal vibration. At the presenttime, no product, other than the device described herein, exists thatwill simultaneously cut roof membrane, insulation and fasteners securingthe membrane in place.

It is another object of the present invention to provide a roof membraneand insulation removing device of the type described that is compact insize. The device is easy to position on a roof and, once there, is farless likely to damage to roof decking than larger machines.

It is an additional object of the present invention to provide a deviceof the type described that has a self-contained power source so it doesnot need to be tethered by cables to a remote generator or electricalgrid thus making the device very maneuverable.

It is a further object of the invention to provide a device of the typedescribed that is self-leveling, retaining its cutting blades inposition for optimum cutting regardless of the bumps, trash and othersurface irregularities that the device may roll over. The result isstrips of membrane and insulation of even width and thickness that arequickly cut from a roof.

It is an object of the invention to provide improved features andarrangements thereof in a roof membrane and insulation removing devicefor the purposes described that is inexpensive to manufacture anddependable in use.

Briefly, the device in accordance with this invention achieves theintended objects by featuring a wheeled frame having a pair ofrearwardly extending handlebars for steering by a walking attendant. Afirst pair of cutting blades is secured to the front of the frame. Eachof the first cutting blades is rotatable about a substantially verticalaxis. A second pair of cutting blades is secured to the front of theframe on opposite sides of the first cutting blades. Each of the secondcutting blades is rotatable about a substantially horizontal axis. Aprime mover is secured to the frame for rotating the first and secondcutting blades. Between the second cutting blades is secured a rampassembly upon which stripped roofing materials are collected fordisposal.

The foregoing and other objects, features and advantages of the presentinvention will become readily apparent upon further review of thefollowing detailed description of the preferred embodiment asillustrated in the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention may be more readily described with reference tothe accompanying drawings, in which:

FIG. 1 is a side view of a roof membrane and insulation removing devicein accordance with the present invention having its hydraulic fluidconduits detached for the sake of drawing simplicity.

FIG. 2 is a top view of the roof membrane and insulation removing deviceof FIG. 1 having its hydraulic fluid conduits detached.

FIG. 3 is a rear view of the roof membrane and insulation removingdevice having its hydraulic fluid conduits detached.

FIG., 4 is a schematic diagram of the hydraulic system of the roofmembrane and insulation removing device.

Similar reference characters denote corresponding features consistentlythroughout the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the FIGS., a roof membrane and insulation removingdevice in accordance with the present invention is shown at 10. Device10 includes a wheeled frame 12 having a pair of handlebars 14 at itsrear for steering by a walking attendant. At the front of frame 12 aresupported a first pair of cutting blades 16 and 18 being rotatable aboutsubstantially vertical axes. On opposite sides of blades 16 and 18 is asecond pair of cutting blades 20 and 22, these being rotatable about asubstantially horizontal axis. A pair of hydraulic motors 24 and 26 andspin blades 16-22 so that such can slice into and through a roofmembrane, foam insulation and penetrating fasteners. Another motor 28rotates a pair of wheels 30 to mover device 10 over a roof. During use,debris severed from a roof by device 10 is collected for periodicdisposal on a ramp assembly 32 positioned at the front of frame 12.

Frame 12 has a front portion 34 and a rear portion 36 joined together bya pivot pin 38 that permits portions 34 and 36 to twist relative to oneanother to accommodate uneven rolling surfaces. Front portion 34 is anopenwork box having a pair of lower side rails 40 and a pair of upperside rails 42 extending forwardly from a back plate 44 penetrated bypivot pin 38. Similarly, rear portion 36 is an openwork box with a frontplate 46 through which pin 38 pivotally extends. A pair of retainingpins 48, secured to plate 44 beneath pin 38, penetrate arcuate slots 50in plate 46 and serve as a stop to prevent excessive, relative twistingof portions 34 and 36.

A cutting blade carrier 52 is pivotally fastened to front portion 34. Asshown, carrier 52 has a pair of pivot arms 54 joined at their front endsby a carrier bar 56 and joined at their rear ends by a tie bar 58 and attheir midpoints by a medial bar 59. Pivot pins 60 fasten arms 54 attheir midpoints to the front ends of lower side rails 40. Threaded rods62 extend outwardly from the rear ends of arms 54 and penetrate slottedbrackets 64 provided on rails 40 rearwardly of pins 60. Nuts 66 onthreaded rods 62 are clamped against brackets 64 to fix the inclinationof carrier bar 56 and hence the height of blades 16-22 carried thereby.

A pair of rotatable wheels or casters 68 is secured to tie bar 58 andmaintain front portion 34 and blade carrier 52 at a predetermined heightabove a supporting surface. Casters 68 each include a threaded shaft(not shown) that threadably engages a socket within tie bar 58. Bymanual rotation of the shaft in the socket, the distance from the bottomof casters 68 to tie bar 58 can be varied as desired by a user thusproviding additional means for adjusting the cutting height of device10.

Each of cutting blades 16 and 18 is circular in outline and includes aperipheral edge having small teeth or, in the alternative, beingimbedded abrasives for cutting purposes. Cutting blades 16 and 18 aresecured to the bottom ends of stub shafts 70 that rotate in journalbearings 72 affixed to carrier bar 56. Shafts 70 retain sprocket gears74 between bearings 72 and blades 16 and 18. Each of the gears 74 isengaged with an endless chain 76 that, when moved as described below,causes blades 16 and 18 to be rotated at high speed.

Chain 76 extends rearwardly from sprocket gears 74 and is looped arounda sprocket gear 78 affixed to the drive shaft 80 of hydraulic motor 24.Motor 24 is affixed to medial bar 59. Thus, when carrier 52 is pivotedup or down on pivot pins 60, motor 24 and gears 74 and 78 move togetherto prevent the binding of chain 76.

Cutting blades 20 and 22 are like blades 16 and 18 in that they possesseither teeth or abrasives along their circular peripheries for cutting.Preferably, blades 20 and 22 are secured to stub shafts 82 that rotatein journal bearings 84 carried between paired support arms 86 whose rearends are fastened to the sides of ramp assembly 32. On shafts 82,between paired arms 86, are secured sprocket gears 88. The gears 88 areengaged with endless chains 90 that are employed to rotate shafts 82 andblades 20 and 22.

Ramp assembly 32 is affixed to the front of portion 34 of frame 12 tocollect strips of roofing membrane cut during use of device 10. Rampassembly 32 has a ramp 33 from which a number of tines 35 projectdownwardly and forwardly. Ramp 33, as illustrated, has a downwardlysloping forward portion 33 a that elevates cut membrane and insulationonto a horizontal rearward portion 33 b as device 10 moves forward.Tines 35 extend downwardly and forwardly from forward portion 33 a tolift just-cut membrane and insulation onto forward portion 33 a.

Chains 90 extend rearwardly from sprocket gears 88 and are looped aroundsprocket gears 92 affixed to the opposite ends of a rotatable shaft 94.Shaft 94 is carried by journal bearings (not shown) mounted upon siderails 40. Adjacent one of these journal bearings, a sprocket gear 96 isaffixed to shaft 94. Looped around gear 96 is an endless chain 98 thatextends rearwardly to engage a sprocket gear 100 affixed to thehorizontal drive shaft 102 of hydraulic motor 26. Motor 26 is mountedupon the bottom of front frame portion 34.

Drive wheels 30 are rotatably supported at the rear of rear portion 36of frame 12 by a rotatable shaft 104. A drive wheel 30 is secured toeach of the opposed ends of shaft 104 for retaining rear portion 36above a supporting surface 106. A sprocket gear 108 is secured to shaft104 adjacent one wheel 30. An endless chain 110 engages gear 108 andextends forwardly therefrom to engage a sprocket gear 112 affixed to thehorizontal drive shaft 114 of hydraulic motor 28. Motor 28 is mountedupon the bottom of rear frame portion 36.

A prime mover being an internal combustion engine 114 is mounted atopfront portion 34 of frame 12 so as to power a two-stage pump 116. Asshown, pump 116 is fastened directly to engine 114 and has two,separate, pumping units 116 a and 116 b being capable of deliveringseparate streams of hydraulic fluid under pressure at predetermined flowrates. Pumping unit 116 a has a fluid inlet and a fluid outlet that donot communicate directly with the fluid inlet and outlet of pumping unit116 b.

While engine 118 is running, hydraulic fluid is delivered from areservoir 118 to pumping units 116 a and 116 b through a suction conduit120. Hydraulic fluid is discharged from pumping unit 116 a into adischarge conduit 122 for delivery to motors 24 and 26. Dischargeconduit 122 is provided with a manually operated valve 124 thatselectively permits the flow of hydraulic fluid to motors 24 and 26connected in series with reservoir 118. (Note: bypass conduitspermitting the continuous pumping of fluid by pump 116 are not shown inthe FIGS. for the sake of simplicity.) With hydraulic fluid flowingthrough motors 24 and 26 such will operate to rotate drive shafts 80 and102 and cutting blades 16-22 through the transmission system previouslydescribed. Hydraulic fluid exiting motors 24 and 26 is returned toreservoir 118 via return conduit 126.

Hydraulic fluid is delivered from a reservoir 118 to motor 28 through asuction conduit 128 while engine 118 is operating. Hydraulic fluid isdischarged from high-pressure pumping unit 116 b into a dischargeconduit 128 for delivery to motor 28. Discharge conduit 128 is providedwith a manually operated valve 130 that controls the flow of hydraulicfluid to motor 28. Valve 130 is shown in FIG. 4 to be situated so thatits segment N is engaged with conduit 128 whereby hydraulic fluid flowsto and from valve 130 into return conduit 132 without accomplishinguseful work meaning that device 10 remains in neutral or at rest. Shouldvalve 130 be shifted so that its F segment is engaged with conduit 128,hydraulic fluid is permitted to flow to motor 28 to rotate shaft 104 andwheels 30 to move device 10 forward. Finally, if valve 130 be shifted sothat its R segment is engaged with conduit 128, hydraulic fluid ispermitted to flow to motor 28 to rotate shaft 104 and wheels 30 to movedevice 10 backward or in reverse.

To avoid overheating the hydraulic fluid, a portion of its flow isdiverted from return conduit 132 to a cooler 134 mounted on handlebars14. After the hydraulic fluid passes through cooler 134, it isdischarged into reservoir 118. Once in reservoir 118, the hydraulicfluid can be withdrawn to power any of motors 24, 26 and 28.

From the foregoing, it should be appreciated that use of device 10 isstraightforward.

First, device 10 is placed on a supporting surface 106 that wouldnormally comprise the steel decking of a roof atop which is secured awater-resistant membrane and insulation in need of replacement. Next,the membrane and insulation are manually lifted to expose its bottomsurface to blades 16-22 at the start of a cut. Then, valve 128 is set toenergize motor 28 to rotate wheels 30 and drive device 10 forwardly. Theforward movement of device 10 presses blades 16-22 against the membraneand any metallic fasteners used to anchor such to surface 106. Now,valve 124 is opened to energize motors 24 and 26 thereby causing blades16-22 to rotate and cut the membrane, insulation and any exposedfasteners.

Cutting of the membrane and insulation proceeds at a rapid pace withdevice 10 moving at a pace approaching that of a self-propelledlawnmower. The membrane and insulation are cut in long strips having awidth substantially equal to the spacing between blades 20 and 22. Thelength of the cut strips will depend in large part on the type andcondition of the membrane and insulation being worked upon but, may inmany cases, would be measured in tens of feet.

If blades 16 and 18 appear to be scraping upon surface 106 as membraneand insulation removal progresses, they can be raised. To do this, nuts66 merely need to be loosened so that the front of cutting blade carrier52 can be elevated a suitable amount. Similarly, lowering the front endof carrier 52, while nuts 66 are loosened, lowers blades 16 and 18.

Because device 10 is highly maneuverable, the process of removing aroofing membrane and insulation can be accomplished in substantiallyless time than required when using conventional tools regardless of theskill of the user. A job that formerly would have required weeks tocomplete can now be completed in days.

While the invention has been described with a high degree ofparticularity, it will be appreciated by those skilled in the art thatmodifications can be made thereto. For example, the number and locationof cutting blades 16-22 can be increased or decreased to suit the needsof a particular user with additional blades permitting the more rapidremoval of roof membrane. Also, with the attachment of a hydraulic ramto front portion 34 of frame 12, casters 68 can be provided with a powersteering mechanism operated by a user. Therefore, it is to be understoodthat the present invention is not limited to the sole embodimentdescribed above, but encompasses any and all embodiments within thescope of the following claims.

1. A roof membrane and insulation removing device, comprising: a wheeledframe having a pair of rearwardly extending handlebars; a first cuttingblade being secured to the front of said wheeled frame and beingrotatable about a substantially vertical axis; a pair of second cuttingblades being secured to the front of said wheeled frame on oppositesides of said first cutting blade, each one of said second cuttingblades being rotatable about a substantially horizontal axis; and, aprime mover being secured to said frame for rotating said first cuttingblade and said second cutting blades.
 2. The roof membrane andinsulation removing device according to claim 1 further comprising aramp assembly secured to the front of said wheeled frame, said rampassembly including a plurality of lifting tines extending forwardly ofsaid first cutting blade.
 3. A roof membrane and insulation removingdevice, comprising: a wheeled frame having a pair of rearwardlyextending handlebars; a first pair of cutting blades being secured tothe front of said wheeled frame, each one of said first pair of cuttingblades being rotatable about a substantially vertical axis; a secondpair of cutting blades being secured to the front of said wheeled frameadjacent said first pair of cutting blades, each one of said second pairof cutting blades being rotatable about a substantially horizontal axis;and, a prime mover being secured to said frame for simultaneouslyrotating said first pair of cutting blades and said second pair ofcutting blades.
 4. The device according to claim 3 wherein said wheeledframe includes a front portion and a rear portion capable of relativepivoting about a substantially horizontal axis, said front portionsupporting said first pair of cutting blades, said second pair ofcutting blades and said prime mover, said front portion having castersretaining such above the ground and said rear porting having wheelsretaining such above the ground.
 5. The device according to claim 3further comprising a ramp assembly secured to said front portion of saidframe, said ramp assembly including a plurality of lifting tinesextending forwardly of said first cutting blade.
 6. A roof membrane andinsulation removing device, comprising: a frame having a front portionand a rear portion capable of relative pivoting motion about asubstantially horizontal axis, said front portion being supported by afirst pair of wheels and said rear portion being supported by a secondpair of wheels, a pair of rearwardly extending handlebars being securedto said rear portion of said frame; a first pair of circular cuttingblades being secured side-by-side to said front portion of said frame,said first pair of circular cutting blades being coplanar, and each oneof said first pair of circular cutting blades being rotatable about asubstantially vertical axis; a second pair of circular cutting bladesbeing secured to opposite sides of said front portion of said frameforwardly of said first pair of cutting blades, each one of said secondpair of circular cutting blades being rotatable about a substantiallyhorizontal axis; a first hydraulic motor being secured to said rearportion of said frame for rotating said second pair of wheels; a secondhydraulic motor being secured to said front portion of said frame forrotating said first pair of circular cutting blades; and, a secondhydraulic motor being secured to said front portion of said frame forrotating said second pair of circular cutting blades.
 7. The roofmembrane and insulation removing device according to claim 6 furthercomprising a ramp assembly secured to the front of said wheeled frame,said ramp assembly including a plurality of lifting tines extendingforwardly of said first cutting blade.